Superposition-based transceiver apparatus for efficient spectrum utilization in microwave backhaul links

Abstract

The disclosed systems, structures, and methods are directed to a superposition based transceiver. The configurations presented herein employ a plurality of encoders configured to encode a plurality of input digital data streams, wherein each of the plurality of input digital data streams operates at different data rates, a plurality of modulators configured to modulate the plurality of encoded digital data input streams. In addition, a plurality of transmitter filters configured to perform up-sampling and filtering of the plurality of modulated digital data streams, and a signal mixer configured to combine the plurality of up-sampled and filtered digital data streams into a single aggregate digital data stream in a manner such that the single aggregate digital data stream contains spectral characteristics that substantially conform to both a central area and a skirt area of a unified spectral emission mask, as specified by European Telecommunications Standards Institute (ETSI).

What is claimed is: 
     
       1. A superposition-based transceiver, comprising:
 a plurality of encoders configured to encode a plurality of input digital data streams, wherein each of the plurality of input digital data streams operates at different data rates; 
 a plurality of modulators configured to modulate the plurality of encoded digital data input streams, wherein each of the plurality of encoded digital data streams is modulated at a different order of an m-ary modulation scheme in accordance with the respective data rates of each of the plurality of input digital data streams; 
 a plurality of transmitter filters configured to perform up-sampling and filtering of the plurality of modulated digital data streams; 
 a signal mixer configured to combine the plurality of up-sampled and filtered digital data streams into a single aggregate digital data stream such that the single aggregate digital data stream contains spectral characteristics that substantially conform to both a central area and a skirt area of a unified spectral emission mask, as specified by European Telecommunications Standards Institute (ETSI). 
 
     
     
       2. The superposition-based transceiver of  claim 1 , wherein each of the plurality modulated digital data streams is up-sampled in accordance with the respective data rates of each of the plurality of input digital data streams operating at different data rates. 
     
     
       3. The superposition-based transceiver of  claim 2 , wherein each of the plurality of up-sampled digital data streams is filtered in accordance with the respective data rates of each of the plurality of input digital data streams operating at different data rates. 
     
     
       4. The superposition-based transceiver of  claim 1 , wherein the plurality of transmitter filters are configured to operate as root raised cosine (RRC) filters. 
     
     
       5. The superposition-based transceiver of  claim 1 , wherein the plurality encoders are configured to operate as low-density parity-check (LDPC) encoders. 
     
     
       6. The superposition-based transceiver of  claim 1  further comprising a plurality of error rate calculation units configured to calculate at least one of a Bit Error Rate (BER) and Signal-to-Noise ratio (SNR). 
     
     
       7. The superposition-based transceiver of  claim 1  further comprising a plurality of phase noise compensation units configured to mitigate effects of phase distortion due to a dispersive channel. 
     
     
       8. The superposition-based transceiver of  claim 1  further comprising a plurality of equalizers configured to mitigate effects of inter-symbol interference (ISI). 
     
     
       9. The superposition-based transceiver of  claim 8 , wherein the plurality of equalizers are configured to operate in accordance with a Bahl-Cocke-Jelinek-Raviv (BCJR) scheme. 
     
     
       10. A method of superposition-based transmission and reception of digital data streams, comprising:
 encoding a plurality of input digital data streams, wherein each of the plurality of input digital data streams operates at different data rates; 
 modulating the plurality of encoded digital data streams, wherein each of the plurality of encoded digital data streams is modulated at a different order of an m-ary modulation scheme in accordance with the respective data rates of each of the plurality of input digital data streams; 
 up-sampling and filtering the plurality of modulated digital data streams; 
 combining the plurality of up-sampled and filtered digital data streams into a single aggregate digital data stream such that the single aggregate digital data stream contains spectral characteristics that substantially conform to both a central area and a skirt area of a unified spectral emission mask, as specified by European Telecommunications Standards Institute (ETSI). 
 
     
     
       11. The method of  claim 10 , wherein each of the plurality modulated digital data streams is up-sampled in accordance with the respective data rates of each of the plurality of input digital data streams operating at different data rates. 
     
     
       12. The method of  claim 11 , wherein each of the plurality of up-sampled digital data streams is filtered in accordance with the respective data rates of each of the plurality of input digital data streams operating at different data rates. 
     
     
       13. The method of  claim 10 , wherein the up-sampling and filtering the plurality of modulated data input streams are based on root raised cosine (RRC) filters. 
     
     
       14. The method of  claim 10 , wherein the encoding operates in accordance with a low-density parity-check (LDPC) encoding scheme. 
     
     
       15. The method of  claim 10 , further comprising calculating at least one of a Bit Error Rate (BER) and Signal-to-Noise ratio (SNR). 
     
     
       16. The method of  claim 10 , further comprising mitigating phase distortion effects due to a dispersive channel. 
     
     
       17. The method of  claim 10 , further comprising mitigating inter-symbol interference (ISI) effects. 
     
     
       18. The method of  claim 17 , wherein the mitigating of ISI effects operates in accordance with a Bahl-Cocke-Jelinek-Raviv (BCJR) scheme.